Monitoring rotating machinery, for example an AC (alternating current) induction motor, is typically conducted by measuring vibration, current, and/or voltages with sensors attached to the machine and analyzed by a separate processor with analog-to-digital (A/D) converters, signal processing, algorithms, and a communications interface. For motor control or motor protection devices, current sensors are typically embedded in existing power management devices such as a variable speed drive or a motor soft-start device. Alternatively, clamp-on probes may be used for short term monitoring of motor current such as to support diagnostics of the motor windings. A separate sensor box with current sensors may be used to sample motor current. In such cases, sampled current data may be used to diagnose the motor in an apparatus or system separate or remote from the motor. Sampled motor current may be analyzed to also detect faults or process problems with equipment connected to the motor such as a motor-operated valve, motor-driven pump, or gearbox driven by a motor. Techniques and apparatus are needed to reduce the complexity and cost associated with motor monitoring as needed to support the diagnostics and prognostics of a motor.